HTC said on Wednesday some of its smartphones have passed a U.S. customs review, clearing the way for it to ramp up sales in the United States.

Earlier in May sales of HTC's One X and EVO 4G LTE models were delayed due to a requirement for customs inspections after the Taiwanese company lost a patent dispute with Apple.

The company said its phones "met International Trade Commission standards and imports to the U.S. would proceed according to normal processes."

The HTC One X model will be available by AT&T and the EVO 4G LTE by Sprint.

HTC has struggled to compete with Apple's iPhones and Samsung's Galaxy range. In February the company released the One series of models, which feature fast graphic processors and advanced music and photography functions.